Alternating-current signaling apparatus for electric railways.



No. 878,138. 'PATENTED FEB. 4, 1908.

J. s. HOLLIDAY.

ALTBRNATING CURRENT SIGNALING-APPARATUS FOR ELECTRIC RAILWAYS. APPLICATION FILED JUNE 3, 1907.

INVENTOR wrruss'szs a-full, clear, an

'vaiiia, have mvente -f R;ef err ing. to the accompanying drawi is, 'thel nuifieral'fi '--designates the track ra' s,

JOHN; s. HoLLInAy, SIGNALCOMPANYL or VANIA.

or WILKINSBURGfPEN-N ;SWISSVALE, PENNSYLVANIA, A CORPORATION SYLVANIA, ASSIGNOR TO UNION SWlTCH dz OF PENNSYL- nmnnmirmecrinnnm .sierunme arms-ares son EIEOTRIG Runways.

v Specification-6f Letters Patent. mums; and 16m 3. 1907. semi-m. eraser.-

Patented Feb. 4,1908.

"Toall whom it"irwycmwe m;

Be it known that L-Jorm SIHOLLI'DAY," of Wilkinsburg, Allegheny county, Fe 1%.

a new and useful ternatin -Current Si Electric ailways o al' Apparatus 01 'wh i hthe following is being had to the'accomp'anymg drawings, forming part of this'specification,'in-which -l and 2 are. diagrammatic views illustrating .twodifierentforms of my invention; and Fig. 3. is a detail-"view showing another form f. the twmphase n ve? vice. y I

This inv systems for electric railways sion, the object 'beingto provide asy-stem ofsignalin ch-that the propulsion current he'signals orinterfere with v pletes. the-'si naling .tery'23 and aids the s' nal clear. When atrain enters the block, is

cannotoperate their'o oration. M inverition consists essentially in the employment of a two-phase current for signel ng-rii es h f r nsiVeto twowphase currents .i ehicliiare divided into insulated sections, as indicated atj3x; q 1:; A indicates'inductive-honds, which connect the trabkrails'at the-ends ofthe sections. 7

'. -'--5indieatesasi 'le phase generator,-which s pplie t'he-conductonfi, ironiwhichthe cars.

Onother'v les;'-one'-of;whichis indicated diagrammatically-at 7 receivetheir supply xii-propulsion current.

- 8,.des' ates a'two-hasegeneratorfor sup-- plyingt s' urrent, this current bemg carried a mg the" liiie, byf'the three .or conductors 9.

Y Y At one-end of each block or section, is a'ftwo phase transformer" 10;

which steps down thewoltage from that of;

jthefline-tofa suit blelfvaluehfor signahn From this transfoniier therela and is there-connected to one terwith reference to Tim-other two conductors.l4 and 15 from the.

transformer '10? are connected to -the respec t re-t c Thep i r act description, reference ntion has relatioiil'te swag where a single yhase'alternating current s used" for prop ul q together with signal'relays,"

' tothe danger position.

'rnent of the two-phase system, stead of the transformer 10, an auto-transto the middle or common wire. of

-x I the-common w re 11 is lead back to the other e'ndofthe blockto each, other, asindicated;

0f he coils or windings .12 and 13 are also connected to the res ective track rails by the conduc- 5E tors 16 an 17 The twowindings 12 and 13 -are displaced with reference to each other and are arranged to act inductively upon'a vane 18fwhich-1s pivoted at 19, and which carries a movable contact 20 which cooper- 60 ates with a relatively fixed contact 21 to control-th'esi al actuating circuit 22.. i when t ere is no train in the blockfthe three conductors. One

transformer 10 is connected to the relay by of these consists of e5 the wire 14; the rail to which that wireis con- 2 nected, and the wire 16; the second consists of the wire 15, the other rail, and the wire 1 7;

while the'third conductor consists of the wire closed position "as shown in the figure This 7 closes the contacts at 20. and 21. andcem;

circuit 22 from the batnected, sdthatfany current coming frpm either part-of the transformer is transmitted to-each of the wind 18 and both same phase. ,There is, therefore, no tendency for the rotatingpart of the relay to revolve, and it opensby gravity, breaking the circuit at 21 and allowing the signal to go J 12 and13 of therelay.

. In Fig. 2 I have shown another arrange' in which, 1n-

former 24 is used; In this arrangement "the conductor 11 is replaced-b a connection-25 from one terminal of the re ay coils 12 and 13 the twophasetransmission line 9. This arrange in ent haslthe advantageover-that' shown 1n Fig. 1, that 1t obviates the necessity for the conductor 11 and requires only three wires or conductors for the signaling system.

Instead of using a vane motor dfthe form shown in Figs. l-and 2:1 may employ a motorsuch as shown-in Fig; 3, consisting of a squirrel cage ,armature 26 surrounded by four or morecoils ojr windings 27 and 28. When this motor isused, the two coils 27 will be co'nnected to receive one phase of the two-phasejcurrent, and the two coils28 connected'to receive the other phase.

11.. Underthese-conditionsthe relayis su p- 7.0 'plied'with two-phase current and takes its e two rails gare con- I windings-receive current in the so The advantages of my: invention result from the fact that.it is impossiblev for the I f the potential of' the two track rails ls not the same, current may flow fromone railto the other through the Wire '16, the windings 12 and 13, and the wire 17. Both windings of the relay are then receiving current in the same phase, and there is no tendency to op erate the relay. Incase a rail breaks, current'will be cut off from one winding of the so far as the signaling current is concerned... .Any propulsionv current whichflows through.

the coils will therefore be without effect 11 on;

my invention, since j relay, which will cause the relay to open-and the signal will then go to the danger'p0sition. It will be noted that the we windings. 12

and 13 are infact connected in series across the track rails, so that they arein serieswith respect to any propulsion current which niay flow from one-0f the track rails to the other,

due to differences of potential therein ;;while at the same time,'the coilsare in. parallel in the relay, even though it is of the same equency as the signaling current.

It" will'be "obvious that various changes -maybe,made bythose "skilledin the art in the particular arrangement illustrated, with-' out departing from the spirit and scope of What/I claim is v 1-. In an electric railway system, employmg a single-phase pro ulsion current, a sig-? naling-circuit, a two-p ase generator for supplying the same with two-phase current, and

j a relay having two windings connected one .to each track railand in parallel with respect to the signaling current and in series with I respect, to any propulsion current which may flow through them-from one track rail to the ptherjsubstantially as described.

2. In an alternating-current signaling sysd tem, sectional trackrails, -a .tw0-phase tran 7 missionline, a'two-phase transforinerhaving itsprimarlesconnected to the transmission --l-1 ne.and one termlnal' of each of, lts secondaries connected to 'opposite-track'rails, and a relay hav ng'two wind ngs, one terminal of each of whiclris connected to the transformer. secondaries and, the other terminals of which I are connected; respectively to opposite track rails, sald'wmdings and track rails, and the connections For the windings constituting two each lock substantially 'as descriloedq 3. In alternating current signaling apparatus, a relay havingtwo'windings for'mm Parts of two different permanentlyfclose ropulsion current to 0perate, the signals."

I ing the opp e permanently closed trackcircuits for. my hand.

track circuits for the blocklcontrolled by saidrelay, one of said circuits including one track rail only, and the other circuit includosite track rail only; substantlally as descri d.

f '4; In alternating current .si alin apparatus, a relayhavingtwo win ings Iormm'g parts of two diiiere-nt .jtrack circuits for thefbloc relay, and means Whereby the currents in ermanently closed l; controlled by said stantialiyjasdescribed.

5;. In an alternating current signali syss'aidycircuits are .made gtoldifierin phase subtennjarelay havinggtwdfldings whic "are connected inseriesfacrossfthe track rails, and

in aralle'lfin the signaling circuit,- siibstantia y as described.v-i"' 6.' In signaling apparatus forelectricraiL Way systems, sectional" track rails formln'g part of a two-phas'e signaling circult, each rail being connected to carry onejphase' of the current, and a relay device having two-. gwindings' connected :to 3 the respective -rails and res onsive to the two-phase] current" only;su stantially as describe 7. In signalinga paratus for railway systems, sectional-tra e rails, a relay having two windings connected to opposite track rails, and means-"for maintaining an alternating difference of potential between said ra'lsancl a thirdconductor which completes t e cir cuitof said coils substantially as described.

8. In signaling apparatus for electric railway systems, sectional track rails, a twophase generator, a two-phase auto-transformer connected to the generator and to, 0pposite track rails, .and'a. relay having-two windings, each of which is connected to one scribed In. testimony-whereof have hereunto set I JOHN. s. HOLLIDAY. Witnesses: a

vJOHN L. HOFFMAN,

J. E. SKIPP.

phase'with-each other substantia y as del I I I 

